Rust inhibiting material



Patented Sept. 2, 1952 UNITED sT rEs ATENT-"OFFICE- stead N. comma, Winnetka, Ill. No Drawing. :Applic a tion August 3, 1949,

Serial No. 108,435

a l Thep'resent' invention relates to adapted to be applied to the surface of iron or steel members as a priming coating to prevent rust and to stop any rusting action which mayhave started prior to the application of the coat-- In conventional rust inhibitive primers the pi ments are incorporated in vehicles depending primarily on oxidation for drying to produce a. somewhat elastic film binding the particles of pigment together in the coating. When corrosive elements, such .as moisture contaminated. with chemicals [from the atmosphere, pass through the coating, the coating readily peels off to expose the metal surface to rusting action. I'he time when deterioration of the metal surface sets in, and to what extent, depends upon many factors such as preparation of the surf-ace to be treated, the number of coat of primer applied to the surface, location of'the surface to be treated, and upon many other factors.

Among the objects of the present invention'is to provide preparations having n'ovel properties coating the same will not peel off when subjected to the corrosive action of moisture contaminated with chemicals from the atmosphere.

A further object of the present invention is to provide novel rust inhibiting preparations particularly adapted for forming moisture resist-' ing'an-d rust preventive coatings, yet being capable of holding finishing coats of ordinary types of paint when applied over the same. e

Other objects, features, capabilities and advantages are comprehended by the invention, as will later appear and as are inherently possessed thereby.

Preparations made in accordance with the present invention are products resulting from the action of a fatty acid, or a mixture of fatty acids, with a lead oxide which is preferably litharge, and sulfur. As illustrative of the invention, the fatty acid content, which is preferably 10 Claims. (Cl. 106-44) preparations- 2 agent to the proper consistency for application as a priming coat to metal surfaces, such as iron and steel. Whensuch a coating is subjected to corrosive constituents .in the atmosphere such as sulphuric acid, the acid first reacts with the lead oleate to form oleic acid, which acts as a wetting agent to soften the priming coat and to cause the same to flow into intimate contact with the metal surface to protect the same from the moisture laden with corrosive elements. Furthermore, the lead oleate and lead sulphide in the preparation provide a continuous supply of lead upon reaction of the sulphuric acid with the lead oleate and lead sulphide in the preparation, to form the insoluble lead sulphate, which acts to render the coating effective in inhibiting the f-or mation of rustover a long period of time.

The fatty acids, or-a mixture thereof, the lead oxide, preferably in the form of 'litharge, and sulphur, may be 'compoundedin varying amounts by weight, as hereinafter more fully disclosed, to

olei'c acid, is mixed with litharge and sulphur" produce preparations having the desired char acteristics as a primer. The following examples exemplify preparations: which meet the requirementsfor a primer of the type herein disclosed and showthe wide range in which these componets maybe mixed toprodu'ce the resulting'preparations:

EXAMPLE I Approximate percent by weight lbs. Oleic acid 100 Litharge 30 22 Sulphur '4 3 EXAMPLE 'II 1 lbs. Oleic acid 66 Litharge. 45 30 Sulphur; 6 4

EXAMPLE III T lbs. Oleic acid 100 x 67' Litharge. 45 i0 Sulphur 4 3 EXAMPLE IV lbs. Oleicscid 100 59-5 Litharge 60 35. 5 Sulphur 8 5.0

EXAMPLE V lbs. Oleic acid 100 54 Litharge 75 41 Sulphur 5 EXAMPLE VI Oleic acid 100 49 Litharge. 90 45 Sulphur 12% 6 EXAMPLE VII lbs. Oleic acid 100 '61 Litharge 60 36. 5 Sulphur 4 2.5

EXAMPLE VIII lbs. Olcic acid 100 47 Litharge 100 47 Sulphur 14 s EXAMPLE ix lbs. Oleic acid- 100 43 Litharge. 115 50 Sulphun- 1s 7 lbs.

- In making the preparations from the materials setv forth in Examples I and H, the oleic acid and sulphur are placed within a kettle or drum and heated to a temperature between 400 and 500 F. during which time the materials shouldbe mixed by a mechanical-mixer or stirrer. '-When a temperature between 400 and 500 F. has been reached the litharge is stirred into thev mix and the reaction between the oleic acid, litharge and sulphur allowed .to continue to completion; According to this particular method it appearsthat a substantial amount of lead oleate is formed which has a tendency to make the final product somewhat harder than that obtained by following the second approved process for making the preparations in accordance with the invention. When the reaction between the components has been completed a volatile thinner in an amount to give the desired consistency to the final preparation is added While stirring the mass untilthe same is cooled to atmospheric temperature.

In making preparations from the materials in the amounts indicated in Examples III to X, the oleic acid, sulphur and litharge are heated in a kettle or drum to a temperature of between 400 and 500 F., during which time the materials are mechanically mixed or stirred. In accordance with this procedure the oleic acid and sulphur are initially mixed together and when the sulphur has melted at a temperature approximating 300 F. the lead oxide is gradually stirred into the mix and the temperature allowed to rise to between 400 and 500 F. The reaction between these materials is allowed to continue to completion after which avolatile thinner in an amount to give the desired consistency to the final prep- In the illustrative example the amount of volatile thinner used is adjusted to produce a. product or preparation having the desired consistency to facilitate the application thereof as a coating to metal surfaces. Such volatile thinner may comprise coal tar solvents, such as naphtha, xylol, toluol, petroleum solvents, such as mineral spirits and varnish makers and painter-7s naphtha, turpentine and the like; s

The various mixes herein-above set forth when reacted in the manner disclosed produce preparations which are particularly adapted for use as rust inhibiting priming coats for metal surfaces. The preparations may also be mixed with other pain-ts to increase the water and chemical resisting properties thereof. While a number of illustrative examples of the invention are set forth hereina'bovc, Example VlIl'. has been found particularly desirable as a coating material adapted for many uses. In accordance with that illustration,- 150 lbs-of volatile thinner is stirred into the molten mass while the same is cooled to atmospheric temperature to produce the-final product.

While oleic acid has been designated as a component of the various mixes used in accordance with the examples, nevertheless, the invention contemplates the use of other fatty acids, such as stearic acid, linoleic acid, fatty acids of soya bean oil, linseed oil, fish oil, cotton seed oil, corn oil, palm oil and coconut oil, or mixtures thereof.

It will be apparent from the illustrations as hereinabove set forth and described that suitable preparations may be formed by reacting a fatty acid in an amount varying from approximately 40% to lead oxide in the form of litharge in an amount varying from approximately 22% to 53%, and sulphur in an amount varying from approximately 2.5% to 7% by weight of the initial mix.

While it is known that the final preparation contains lead oleate and lead sulphide,..the reaction between the oleic acid, litharge and sulphur proceeds in such a manner as to produce varying amounts of these two constituents, 'de'' pending upon the relative amountsrof starting materials used, the process followed, and the temperature to which the materials are sub- -lected during the reaction. The relative amounts of lead oleate and lead sulphide in the final preparation determines the constituency of the resulting product. Such mass reaction conditions as prevail to regulate the relative amount of leadolea'te and lead sulphide formed in the resulting preparation are not suflioiently or clearly understood to the extent which warrants a prediction as to the composition of the final product in any given instance.

the final preparation in terms of the starting materials used.

While I have herein described several illustrative examples of the invention, it is to be understood that the invention is not limited,

thereto but may comprehend other preparations, details, features and method steps without departing from the spirit of the invention. v

It is claimed: 1 .1. A rust inhibitive preparation resulting from the reaction of a mixture comprising from approximately 40% to 75% by weight of a mixture of fatty acids each having not less than sixteen carbon atoms in its molecular structure, from. approximately 22% to 53% byweight of lead Oxide, and from approximately 2.5% to 7% by Accordingly, it has been found desirable in the claim structure to define weight of sulphur at a temperature below 500 F.

2. A rust inhibitive preparation resulting from the reaction of a mixture comprising from approximately 40% to 75% by weight of oleic acid, from approximately 22% to 53% by weight of lead oxide, and from approximately 2.5% to 7% by weight of sulphur at a temperature below 500 F.

3. A rust inhibitive preparation resulting from the reaction of a mixture comprising from approximately 40% to 75% by Weight of a fatty acid having not less than sixteen carbon atoms in its molecular structure, from approximately 22% to 53% by weight of litharge, and from approximately 2.5% to 7% by weight of sulphur at a temperature below 500 F.

4. A rust inhibitive preparation resulting from the reaction of a mixture comprising from approximately 40% to 75% by weight of oleic acid, from approximately 22% to 53% by weight of litharge, and from approximately 3% to 7% by weight of sulphur at a temperature below 500 F.

5. A rust inhibitive preparation resulting from the reaction of a mixture comprising from approximately 40% to 75% by weight of oleic acid, from approximately 22% to 53% by weight of litharge, and from approximately 3% to 7% by weight of sulphur at a temperature of from 400 to 500 F.

6. A rust inhibitive preparation resulting from the reaction of a mixture comprising approximately 47% by weight of a fatty acid having not less than sixteen carbon atoms in its molecular structure, approximately 47% by weight of lead oxide, and approximately 6% by weight of sulphur at a temperature of from 400 to 500 F.

7. A rust inhibitive preparation resulting from the reaction of a mixture comprising approximately 47% by weight of a fatty acid having not less than sixteen carbon atoms in its molecular structure, approximately 47% by weight of litharge, and approximatel 6% by Weight of sulphur at a temperature of from 400 to 500 F.

75% by weight of a fatty acid having not less than sixteen carbon atoms in its molecular structure, from approximately 22% to 53% by weight of lead oxide and from approximately 2.5% to 7% by weight of sulphur at a temperature of between 400 F. and. 500 F., allowing said reaction to proceed to completion, and adding. a volatile thinner to the reaction preparation.

10. A rust inhibitive preparation resulting from the reaction of a mixture comprising from approximately 40% to 75% by weight of at least one ofthe fatty acids selected from the group consisting of oleic acid, stearic acid, linoleic acid, palmitic acid, linolic acid, linolenic acid and clupanodonic acid, from approximately 22% to 53% by weight of lead oxide, and from approximately 2.5% to 7% by weight of sulphur ata temperature below 500 F.

HOWARD N. COPTHORNE.

REFERENCES CITED The following references are of record in the .file ofthis patent:

UNITED STATES PATENTS Shields May 20, 

1. A RUST INHIBITIVE PREPARATION RESULTING FROM THE REACTION OF A MIXTURE COMPRISING FROM APPROXIMATELY 40% TO 75% BY WEIGHT OF A MIXTURE OF FATTY ACIDS EACH HAVING NOT LESS THAN SIXTEEN CARBON ATOMS IN ITS MOLECULAR STRUCTURE, FROM APPROXIMATELY 22% TO 53% BY WEIGHT OF LEAD OXIDE, AND FROM APPROXIMATELY 2.5% TO 7% BY WEIGHT OF SULPHUR AT A TEMPERATURE BELOW 500* F. 